# Project Gutenberg Ebook Search (Gutendex)

> Project Gutenberg Ebook Search (Gutendex) is a paid API for AI agents from clonecho.builda.company, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-13).

Search Project Gutenberg's public-domain ebook catalog by keyword, returning book titles, authors, and download counts as JSON.

## Facts

- Endpoint: POST https://clonecho.builda.company/x402/s/gutendex-search
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/project-gutenberg-ebook-search-gutendex-0d8a2498
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ILBFAle_yFw3pkGMNSFm_

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability project-gutenberg-ebook-search-gutendex-0d8a2498 -d '<json body>'
```

Example prompt: Can you search Project Gutenberg for public-domain ebooks about 'Sherlock Holmes' and show me the titles, authors, and how many times each has been downloaded?

## When to prefer this

Use this endpoint when you need to search Project Gutenberg's public-domain ebook catalog by keyword, author, or title and want structured JSON results with author names and download popularity data. Prefer this over scraping Gutenberg directly or using a general web search when you need machine-readable structured book metadata.

## Known failure modes

- Empty result set if keyword matches no books in the catalog
- HTTP 402 if payment header is not provided or USDC balance is insufficient
- Malformed or missing query parameter returns an error or empty results
- Timeout if Gutendex upstream API is slow or unavailable

## How this service works

Search Project Gutenberg's public-domain ebook catalog by keyword {q}, with authors and download counts. Query: ?q= Returns JSON.

## Output

A JSON array of matching public-domain ebooks from Project Gutenberg, each including title, author(s), and download count metrics, filtered by the provided keyword query.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/project-gutenberg-ebook-search-gutendex-0d8a2498/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from clonecho.builda.company](https://www.zero.xyz/host/clonecho.builda.company/llms.txt)